How is NADP reduced?Watch
For example in the Kreb's cycle
PSII and PSI operate in electrical series to couple oxidation of H2O with reduction of NADP.
In animals, during the pentose phosphate pathway [an alternative to glycolysis that occurs e.g. in the liver and in the mammary gland], glucose 6 phosphate (G6P) is oxidized as NADP+ is reduced to NADPH, so the H comes from G6P [the process involves several steps, of which one intermediary is xylulose phosphate.
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